Two-dimensional X-ray diffraction characterization of the growth mechanism of double perovskite-structured nanoparticles in thin films prepared via metal-organic decomposition

ABSTRACT: Doping of nanoparticles is one of the effective methods in order to obtain nanocomposite thin films with significantly improved performance. The complete understanding of nucleation and growth mechanism for...

In Situ EBSD Study on the Microstructural Transformation of the Ni5W Substrate for Coated Conductors

The microstructure and texture evolution of Ni-5 at%W (Ni5W) alloy substrates were investigated by in situ tensile testing along the rolling direction (RD), transverse direction (TD), and at 45° to the RD (45°-RD), as well as by electron backscatter diffraction characterization. The tensile stress direction had a significant influence on the texture evolution. The cubic texture in the Ni-5 at%W alloy exhibited severe degradation when the tensile angle was 45°-RD. In contrast, the cubic texture was relatively stable under high deformation along the RD or TD. It was found that the slip line system in the 45°-RD specimen was the key to the contrasting behavior. The effect of the tensile testing angle on the cubic texture evolution for Ni–W substrates was investigated, and the corresponding effect on the superconducting properties of coated materials was studied.

Adsorption, kinetics and thermodynamics studies of methyl orange dye sequestration through chitosan composites films

Different films comprising pure chitosan (CS) and chitosan coated sodium zeolites composites films designated as CSZ1, CSZ2, CSZ3 and CSZ4 respectively are presented here for the sequestration of MO dye. The as-synthesized films were characterized by using FSESM, XPS XRD, and TGA analysis. The sequestration of methyl orange dye (MO) was studied under various adsorption parameters i.e. pH effect, reaction temperature, catalytic dosage, interaction period, and original dye concentration in batch experiments. The adsorption power of MO dye sequestration in the presence of CSZ3 was 287 mg g^-1 higher than the fine CS (201 mg g^-1), and lowest for CSZ4 (173 mg g^-1). The experimental data is fitted in the pseudo-second order of chemical kinetics. The Freundlich and Langmuir adsorption models were used on behalf of the analysis of experimental data that revealed multilayered adsorption of MO dye. Kinetics, equilibrium and thermodynamic process were discussed in detailed, suggesting the endothermic and spontaneous process of the adsorption of MO dye on the exterior of films. The present work is general for the MO adsorption, however, it can be applied on large scale applications and can be easily adjustable in the water purification assemblies.

Synthesis, Characterization, and Multifunctional Applications of Cu-Fe and Ni-Fe Nanomaterials

Cu-Fe and Ni-Fe nanomaterials (NMs) were successfully obtained via a coprecipitation route. Phase analysis and the micro- and physiochemical structure studies for the as-synthesized NMs were carried out with advanced techniques such as TEM, SEM, XRD, XPS, BET, DRS, TGA, and FTIR. Particles with size ranging from 25 to 70 nm were displayed by all the characterization techniques. A surface area of ∼4.48 and 36.52m²/g and band gap energies of ∼1.79 and 1.48 eV were calculated for Cu-Fe and Ni-Fe NMs, respectively. Saturation magnetization (Ms) ∼77.95 emu/g (for Cu-Fe) and 27.70 emu/g (for Ni-Fe) revealed superparamagnetism for both the NMs. The presence of ethanol and methanol as sacrificial agents contributed effectively toward electrocatalytic H-evolution as compared to pure NMs. Furthermore, under solar light irradiations, Cu-Fe and Ni-Fe NMs displayed 85 and 91% degradation during a time interval of 50 and 110 min, respectively, for toxic industrial methylene blue (MB) dye. Different operational variables such as the catalyst amount, pH values, various scavengers, reusability, and stability were thoroughly investigated. Moreover, in situ analysis was carried out in order to determine the mechanism for degradation reactions. A detailed study about various applications categorized the synthesized NMs as efficient candidates for toxic industrial waste cleanup and energy production at an industrial level.

Correlation between the hemoporfin-mediated photodynamic treatment response and the dermoscopy vascular pattern in patients with a port-wine stain: a prospective study

BACKGROUND

Vascular targeted photodynamic therapy (PDT) is a novel and promising therapy for the treatment of port-wine stains (PWS). There has been little prior exploration to our knowledge of how the dermatological vascular pattern may predict the response to PDT.

OBJECTIVES

To analyse whether the vascular pattern classifications of PWS by dermoscopy can predict the efficacy of PDT.

METHODS

This prospective cohort study included 163 patients with a clinical diagnosis of PWS who were treated twice with hemoporfin-mediated photodynamic therapy (HMME-PDT) at two-month intervals and followed up for 6 months. The vascular manifestations of dermoscopy with PWS were independently classified into 8 categories by 3 dermatologists. Images of the lesions were taken using VISIA, and the vascular patterns were imaged by dermoscopy by the same investigator. Images were captured before and after each treatment. The efficacy was evaluated with pre- and post-treatment VISIA images, and correlations between efficacy and vascular patterns were analysed by four dermatologists in a blinded and independent manner, between 10 January 2019 and 11 December 2019.

RESULTS

In the dermoscopy images for the whole cohort, dotted and globular vessels (15.3%), short clubbed vessels (18.4%) and curved vessels (12.9%) were highly associated with cure and beneficial treatment effects. Pale halos surrounding brown dots (8.0%) and arborizing vessels (9.8%) were mainly correlated with skin lesion alleviation. Mixed vessels (12.9%), a grey-whitish veil (11.7%) and reticular patterns (11.0%) were mainly associated with no effect. The differences between each subgroup were statistically significant (P = 0.000).

CONCLUSIONS

There is a clear correlation between the efficacy of PDT and the dermoscopy pattern in patients with PWS. Dermoscopy may therefore provide very useful clinical information prior to treatment in these cases. In addition, the vascular manifestations of PWS determined by dermoscopy help to predict response to PDT and manage patient expectations.

In Situ EBSD Study of Stable Cube Texture in an Advanced Composite Substrate Used in YBCO-Coated Conductors

Advanced Ni8W/Ni12W/Ni8W alloy composite substrates used in YBCO-coated conductors with a strong cube texture and high yield strength have been fabricated, and a CeO2 buffer layer film was successfully deposited on the composite substrates. Through in situ tensile testing coupled with electron backscattered diffraction (EBSD) analysis, the stability of the cube texture of Ni8W/Ni12W/Ni8W alloy composite substrates has been investigated. The stress-strain curve shows that the yield strength (at 0.2% strain) of the composite substrates exceeds 250 Mpa. The orientation of grains and boundaries on the surface of the substrates was almost unchanged, while the strain exceeds 0.2%, which indicated that the composite substrates are adequate for depositing buffer layers and YBCO layers by the reel-to-reel process.

Scaling Behavior of Quasi-One-Dimensional Vortex Avalanches in Superconducting Films

Scaling behaviour of dynamically driven vortex avalanches in superconducting YBa2Cu3O7-δ films deposited on tilted crystalline substrates has been observed using quantitative magneto-optical imaging. Two films with different tilt angles are characterized by the probability distributions of avalanche size in terms of the number of moving vortices. It is found in both samples that these distributions follow power-laws over up to three decades, and have exponents ranging between 1.0 and 1.4. The distributions also show clear finite-size scaling, when the system size is defined by the depth of the flux penetration front - a signature of self-organized criticality. A scaling relation between the avalanche size exponent and the fractal dimension, previously derived theoretically from conservation of the number of magnetic vortices in the stationary state and shown in numerical simulations, is here shown to be satisfied also experimentally.

Synthesis of AgNPs coated with secondary metabolites of Acacia nilotica: An efficient antimicrobial and detoxification agent for environmental toxic organic pollutants

This study concentrates on biosynthesis of Silver Nanoparticles (AgNPs) from stem extract of Acacia nilotica (A. nilotica). The reaction was completed at a temperature ~40-45 °C and time duration of 5 h. AgNPs were thoroughly investigated via advanced characterization techniques such as UV-Vis spectrophotometry (UV-Vis), Fourier Transform Infrared spectroscopy (FTIR), X-ray Diffractometry (XRD), Field Emission Scanning Electron Microscopy (FESEM), High Resolution Transmission Electron Microscopy (HRTEM), X-ray Photoelectron Spectroscopy (XPS), Thermo Gravimetric Analysis (TGA), Diffuse Reflectance Spectroscopy (DRS), Brunner-Emmett-Teller (BET), Dynamic Light Scattering (DLS), and Zeta potential analysis. AgNPs with average size below 50 nm were revealed by all the measuring techniques. Maximum surface area ~5.69 m²/g was reported for the as synthesized NPs with total pore volume ~0.0191 mL/g and average pore size ~1.13 nm. Physical properties such as size and shape have changed the surface plasmon resonance peak in UV-visible spectrum. Antimicrobial activity was reported due to denaturation of microbial ribosome's sulphur and phosphorus bond by silver ions against bacterium Methicillin Resistant Staphylococcus aureus (MRSA) and fungus Candida Albican (CA). Furthermore, AgNPs degraded toxic pollutants such as 4-nitrophenol (4-NP), 2-nitrophenol (2-NP) and various hazardous dyes such as Congo Red (CR), Methylene Blue (MB) and Methyl Orange (MO) up to 95%. The present work provided low cost, green and an effective way for synthesis of AgNPs which were utilized as potential antimicrobial agents as well as effective catalyst for detoxification of various pollutants and dyes.

The precursor manipulation of La2Zr2O7 epi-layers annealed by rapid thermal annealing

This paper reports on the epitaxial growth of a La₂Zr₂O₇ (LZO) buffer layer on the cube-textured Ni-5 at.%W substrate with nitrates as the precursor salts.

Distinguishing crystallographic misorientations of lanthanum zirconate epilayers on nickel substrates by electron backscatter diffraction

Electron backscatter diffraction (EBSD) was used for distinguishing crystallographic orientations and local lattice misfits of a La(2)Zr(2)O(7) (LZO) buffer layer epitaxially grown on a cube textured Ni-5.%W (Ni-W) substrate for a YBCO superconductor film. Orientation data were obtained from the LZO epilayer using low energy primary electrons (5keV) and from the Ni-W substrate by increasing the voltage to 15keV. In-plane and out-of-plane orientations of the LZO epilayer were revealed with respect to its Ni-W substrate. A strong {100} 〈011〉 rotated-cube texture in the LZO epilayer was formed on the {100} 〈001〉 cube-textured Ni-W substrates. LZO and Ni in-plane crystallographic axes are related by an expected 45° rotation. The step-misorientations and the local misfit strains between the LZO epilayer and the substrate were also analyzed.

Ethanol-induced neurodegeneration in NRSF/REST neuronal conditional knockout mice

The transcription regulator, neuron-restrictive silencer factor (NRSF), also known as repressor element-1 silencing transcription factor (REST), plays an important role in neurogenesis and various neuronal diseases such as ischaemia, epilepsy, and Huntington's disease. In these disease processes, neuronal loss is associated with abnormal expression and/or localization of NRSF. Previous studies have demonstrated that NRSF regulates the effect of ethanol on neuronal cells in vitro, however, the role of NRSF in ethanol-induced neuronal cell death remains unclear. We generated nrsf conditional knockout mice using the Cre-loxP system to disrupt neuronal expression of nrsf and its truncated forms. At postnatal day 6, ethanol significantly increased the expression of REST4, a neuron-specific truncated form of NRSF, in the brains of wild type mice, and this effect was diminished in nrsf conditional knockout mice. The apoptotic effect of ethanol was pronounced in multiple brain regions of nrsf conditional mutant mice. These results indicate that NRSF, specifically REST4, may protect the developing brain from ethanol, and provide new evidence that NRSF can be a therapeutic target in foetal alcohol syndrome (FAS).

[A case of adult onset phosphoglucomutase deficiency]

A case of 38-year-old male with adult onset phosphoglucomutase (PGM) deficiency was reported. The patient was admitted at Kawamura Hospital (Gifu City) for evaluation of easy fatiguability and exercise-induced weakness of the extremities since he was 20 years old. Physical examination revealed moderate muscle weakness, wasting of extremities, bilateral clubbed fingers and hypoesthesia of distal portion of extremities. Fasting plasma glucose was low (58 mg/dl). Venous concentration of lactate failed to rise after an ischemic forearm exercise test. An epinephrine tolerance test revealed hyperglycemic response. Studies of anaerobic glycolysis in vitro using muscle homogenates with the substrate between glucose-1-phosphate and glucose-6-phosphate showed decreased lactate production. Direct assay of individual muscle glycolytic enzymes demonstrated reduction of PGM activity (15% of normal, n = 12). Biopsy study with PAS staining of quadriceps femoris muscle demonstrated small amount of deeply staining glycogen in subsarcolemmal area. Electron microscopic examination revealed muscle destruction with small amount of glycogen in subsarcolemmal and intermyofibrillar spaces. Sural nerve biopsy showed degeneration of myelinated and unmyelinated fibers but there was no apparent accumulation of glycogen. From the clinical, biochemical and histopathological evidences, the patient might be a rare case of adult onset PGM deficiency.